比例求解器 — 公式

How to Solve a Proportion

Setup

a/b = c/x

Cross-Multiplication

a × x = b × c

x = (b × c) / a

Verification

After solving, check that a/b equals c/x.

计算示例

If 3/4 = 9/x, find x.

  1. 3/4 = 9/x
  2. Cross multiply: 3x = 4 × 9 = 36
  3. x = 36/3 = 12
  4. Check: 3/4 = 0.75, 9/12 = 0.75